Why is my kitchen exhaust fan making a squealing noise?

A squealing or screeching exhaust fan almost always means the drive belt is slipping, worn, or glazed. The belt is still working but losing grip. It will snap within days to weeks. Belt replacement is a quick fix: contact us for pricing.

Is a noisy exhaust fan an emergency?

It depends on the noise. A humming motor that is not spinning is an emergency: your exhaust is not working. Grinding or heavy vibration is urgent: call within 24 hours. Squealing is medium urgency: schedule within the week. All noises mean something is about to fail.

How much does exhaust fan repair cost?

Costs vary depending on the issue: belt replacement is the least expensive fix, while motor replacement costs significantly more. The cost goes up the longer you wait. Contact us for a quote.

Exhaust Fan Making Noise? 5 Causes and When to Call for Service

A noisy exhaust fan isn't just annoying: it's telling you something is about to fail. Here's how to decode the sounds coming from your roof.

1. Squealing or Screeching

What it means: Belt slipping or worn. The belt is loose, glazed, or cracking. It's still technically working but losing grip: your exhaust CFM is dropping.

Urgency: Medium. The belt will snap within days to weeks. Schedule service this week.

Fix: Belt replacement. Contact us for pricing.

2. Grinding or Rumbling

What it means: Bearings are failing. Metal-on-metal contact inside the bearing housing. If you can feel vibration through the roof or hood, it's advanced.

Urgency: High. Failed bearings seize the shaft, which burns out the motor: turning a simple bearing job into a full motor replacement. Call today.

Fix: Bearing replacement. If you wait, motor replacement is significantly more expensive. Contact us for pricing.

3. Loud Vibration or Rattling

What it means: Fan wheel is out of balance. Usually caused by grease buildup on one side of the wheel, a broken blade, or loose mounting hardware. The vibration damages bearings, loosens ductwork connections, and can crack the fan housing.

Urgency: High. Unbalanced vibration causes cascading failures. Schedule within a few days.

Fix: Fan wheel cleaning and rebalancing, or blade repair. Check mounting bolts while you're up there. Contact us for pricing.

4. Clicking or Tapping

What it means: Something is hitting the fan blade: a loose piece of grease, a foreign object, or a blade rubbing the housing. Could also be a failing contactor or relay clicking on and off.

Urgency: Medium-low if intermittent, high if constant.

Fix: Inspection and foreign object removal. If it's a contactor, electrical repair is needed. Contact us for pricing.

5. Humming but Not Spinning

What it means: The motor is getting power but the shaft isn't turning. Either the belt is completely broken (most common), the motor capacitor has failed, or the motor windings are burned.

Urgency: Critical. Your exhaust is not working. No air is being removed from the kitchen. This is an emergency.

Fix: Belt replacement, capacitor replacement, or motor replacement depending on the cause. Contact us for emergency service.

The Bottom Line

Every noise is a warning. The repair cost goes up the longer you wait: a simple belt replacement today prevents a full motor replacement next month. The fan on your roof is running in the harshest conditions: heat, grease, rain, snow, UV exposure. It needs attention. Contact us for a quote.

True Commercial Service diagnoses commercial kitchen exhaust-fan, VFD, controls, and airflow problems across NYC and North Jersey. Send the fan information, symptoms, ZIP code, and rooftop-access details so TCS can confirm fit and availability.

Looking for service? Visit our Kitchen Ventilation Service page or schedule service today.